Nuclear Isomer energy storage and Quantum Nucleaonic Reactors
Nuclear Isomers are an exciting new development in the field of Nuclear physics. They are, essentially, a nuclear storage battery. Just as atoms can have electrons in excited states, atomic nuclei can have nucleons (protons and nuetrons) in excited states as well, but unlike atoms with electrons in excited states, the nucleons can remain in their excited states for extended lengths of time. The excited nucleons can randomly decay on their own, and have representative half-lifes as well. Not all atoms can have stable excited nucleons, and typically larger atoms are more likely to have longer half-lifes of the excited nucleons. But, the theory goes, the nucleons of an atom can be excited to higher energy levels by bombarding them with gamma rays, and then triggered to release their energy on demand by hitting them with lower energy photons, Ultra Violet or X-Rays. These would amount immensely dense energy storage devices, with power densities per unit wieght reaching a theorhetical limit near that of low end fusion reactions!
Best Batteries - 300 Wh/Kg
Fuel Cells (aluminum) - 4,000 Wh/kg
Isomer Nucleonic - 800,000,000 Wh/Kg
Fusion - 90,000,000,000 Wh/Kg
Developments in Isomers
021903 - 'Nuclear-powered' drone aircraft on drawing boards
The 'Nuclear-powered' could be considered a misnomer, as this effect is not necessarily nuclear but is also not chemical. The US Military is performing Feasibility studies on Quantum Necleonic Reactor powered Unmanned Aerial Vehicles. A nuclear UAV would generate thrust by using the energy of these gamma rays to produce a jet of heated air, using this power source, they conclude, could extend the UAV's flight time from hours to months.
from - http://www.newscientist.com/news/news.jsp?id=ns99993406
081301 - Physicists Challenge Reports of Accelerated Decay of Nuclear Excited State
Physicists from the Lawrence Livermore National Laboratory, in collaboration with scientists at Los Alamos and Argonne national laboratories, have new results that strongly contradict recent reports claiming an accelerated emission of gamma rays from the nuclear isomer 31-yr. hafnium-178, and the opportunity for a controlled release of energy. They said "In other words, the X-ray irradiation did not decrease the time it takes for hafnium to decay; a result that Becker and the team claim is consistent with nuclear physics" The nucleonic excitation has nothing to do with the weak nuclear radioactive decay of the host atom. So I am not sure why it matters that the LLNL found that the X-Ray irradiation did not 'decrease the time it takes for hafnium to decay' It shouldnt after all, it should, however, decrease the time it takes for the excited nucleons to decay to a non-excited state.
from - http://www.llnl.gov/llnl/06news/NewsReleases/2001/NR-01-08-05.html
May 1999 - Physics Web - Light plays tricks with nuclei
A good description of the expirement and of note - "...A single nucleus can hold up to several mega-electron-volts. This means that one gram of material could store several giga-joules of energy"
from - http://physicsweb.org/article/world/12/5/3
University of Texas at Dallas - ESSENTIAL FUNDAMENTALS OF QUANTUM NUCLEONICS